title: Spatiotemporal evaluation of water quality incidents in Japan between 1996 and 2007.
abstract: We present a spatiotemporal evaluation of water quality incidents in Japan considering incident numbers, incident causes, pollutant categories, and pollution effects. Water pollution incidents in first-class river systems almost tripled to about 1487 in the 12 years from 1996 to 2007. In addition, oil makes up the largest proportion of pollutants nationwide (76.61%) and the major source of pollution for each region in Japan. Moreover, every category shows a growth trend, especially since 2005. The main cause of incidents was "Unknown" (43%), followed by "Poor working practice" (24%), and then by "Accident" (10%) and "Other" (10%). In Hokuriku, however, the main cause of incidents was "Poor working practice" (36%), which is greater than "Unknown" (30%). Finally, waterworks (approximately 60%) was the largest of four kinds of water supply infrastructure affected by pollution incidents, followed by simplified waterworks. The population affected by offensive odors and tastes peaked in 1990 and has been decreasing. Overall, the results show the characteristics of incidents from 1996 to 2007, with significant implications for adaptation measures, strategies and policies to reduce water quality incidents.
authors.affiliation: Department of Civil and Earth Resources Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan. Electronic address: duan.scut.cn@gmail.com.
authors.forename: Weili
authors.initials: W
authors.lastname: Duan
authors.forename: Bin
authors.initials: B
authors.lastname: He
authors.forename: Kaoru
authors.initials: K
authors.lastname: Takara
authors.forename: Pingping
authors.initials: P
authors.lastname: Luo
authors.forename: Daniel
authors.initials: D
authors.lastname: Nover
authors.forename: Netrananda
authors.initials: N
authors.lastname: Sahu
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Yamashiki
mesh_terms: D004784:Environmental Monitoring; D007564:Japan; D045483:Rivers / Q000737:chemistry; D062211:Spatio-Temporal Analysis; D014874:Water Pollutants, Chemical / Q000032:analysis; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data*; D060753:Water Quality; D014881:Water Supply / Q000706:statistics & numerical data
chemical_list: D014874:Water Pollutants, Chemical
keywords: GIS; Japan; Spatiotemporal evaluation; Statistical analysis; Water quality incidents